by Tabitha Jenkins
If you work in a lab, you will know that feeling when your supervisor says ‘you have it easy, it was never like this back when I was doing lab work…’ To be fair to our supervisors, times have changed and with it, a lot of experiments are easier. The crazy thing is, these changes really have happened overnight. On the other side, advancement in technology means that experimental opportunities have expanded beyond belief, which in my opinion, makes it harder for us to decide which techniques to use. But back to advancements in the lab, I thought I would compare the techniques a little, perhaps making you more prepared next time your supervisor brings it up… I am only mentioning four examples which have come up a lot in my lab experience. I should also mention, I don’t count the snazzy new technology that never existed, I’m talking about the like-for-like technology where the outcome is the same.
1. The Mouth Pipette vs. Gilson pipette
The mouth pipette was one of the most commonly used pieces of lab equipment prior to the 1970s and unsurprisingly was the leading cause of laboratory-derived infections. The pipette used the mouth to measure and transfer liquids. From the 1970s, mouth pipetting was less favourable due to the influx of the hand-held mechanically adjustable pipettes. They were much safer and far more accurate. They can also be calibrated so the volumes are consistent and reliable and a lot more specific, measuring to the microliter. Obviously, today, mouth pipettes are not allowed in laboratories for the very evident reason of potentially ingesting hazardous solutions. It is hardly surprising when people were literally inserting an open-ended capillary tube into their mouths and sucking up different solutions and chemicals.
2. The Water bath PCR machines vs. automated machine
Polymerase chain reaction (PCR) was discovered over 20 years ago in 1983, and since then it has grown exponentially with major developments in equipment, reagents, sample prep, programs and techniques. Forgetting about the advances and work done on polymerases (the enzymes that assemble DNA and RNA molecules) for one moment and let’s look at the actual process. When the technology was first discovered, DNA application using PCR was time-consuming and laborious, the scientist had to stand, transferring their tubes from one water bath to another in cycles for hours, all rather tedious I can imagine. Whereas today, we can set up a PCR, place it on the thermal cyclers, and continue with other work. Technology has definitely made PCR a very easy, almost an ‘extra’ to your day, something you can slot into a jam packed day of science. The first thermal cycler, the TC1 DNA thermal cycler, became available in 1987, and even that was only if the lab could afford it!
3. The Dark Room Image developing vs. Phospho-imager
This one is a bit different as I am sure many labs still use darkroom development of western blots. However, the technology has still changed making it easier with alternative methods to developing westerns. Chemiluminescence detection methods depend on the incubation of the western blot with a substrate that will luminescence when exposed to the reporter on the secondary antibody. Today this is made easier by ready-made reagents which can be exposed and developed using an imager – of which there are many on the market – giving you a nice digital image. Originally, the dark room was the only way to develop the western. This requires skill to not over develop or under develop your x-ray films, it also requires skill in finding your way around a very dark room!
4. DNA sequencing vs. Sanger Over-night primer extension sequencing
The first full DNA genome was sequenced in 1977 using radioactive labelling of the DNA and then X-rays to visualise fragmented DNA. This was called Maxam-Gilbert sequencing. Over the years, the method of sequencing has changed dramatically. In the early 1980s it was achieved using non-radioactive methods of transferring the DNA molecules in the sequencing reaction mix onto an immobilised matrix during electrophoresis. Then 1987 a method was developed using a novel florescent labelling technique allowing all four bases to be identified in a single lane, then by 1990 this had become large scale sequencing and a lot cheaper to do! Today we have high throughput sequencing, or next generation sequencing which allows for the entire genome to be sequenced. This has gone from a laborious, very hands-on and time consuming method to sequencing results over night!
There have been vast expanses in technology available in the lab and a lot of this technology is continuing to develop, increasing the throughput, making the equipment cheaper and more accessible. So perhaps next time your supervisor makes a comment about how we have it easy, consider they may be right- but only in terms of resources, not in terms of the work load!
I am a PhD student at the University of Nottingham studying helicases in DNA repair. I am currently working at the Biochemical Society with the public engagement and education department. I really enjoy talking about science (any and all science) with the public and would love to see changes in STEM education.